The driving principal behind hydraulic mining, conducted via the induced
fracturing of the earth's surface has been around since the 1850's and the
age of the California Gold Rush.

Because of water's resistance to compression, it is a responsive medium to
pressure. In the middle part of the 1800's surface fracturing was
accomplished by hydraulically pressurizing water contained within a closed
system on a horse drawn wagon or locomotive car and simply expressed
through a hose aimed at an area on the ground targeted for mining. This
simple and portable technique saved a great deal of man hours, so was
greatly favored over more traditional pick and shovel operations.

Like its successor of today, however, it was neither a safe nor tidy
process. Efficiently blasting entire hillsides away in a matter of days,
the process clogged streams and rivers and produced a tide of waste and
devastated farm lands. The practice was finally somewhat subdued in 1882
under the Woodruff v. North Bloomfield Gravel Mining Company case, but the quest for more efficient ways of extracting minerals prevailed, driven by explosive growth and competition among the world's leading political powers.

Throughout the industrial age, mining companies sought to apply and
capitalize on evolving innovations in the practice of hydraulic mining,
eventually coupling the idea of hydraulics with drilling in order to
bypass the surface altogether and introduce a variety of explosives and
fluids beneath the surface of the earth in order to fracture it
underground, theoretically releasing gas and oil from its surrounding
geology.

At its root, hydraulic fracturing is a fairly straight-forward mechanical
process wherein fluids or gases, like CO2 or propane are injected into a
drilled and cased wellbore under extremely high pressure - pressures high
enough to counter the weight of the surface rock, known as overburden, in order to fracture the subsurface rock and encourage natural gas to collect and flow up the wellbore, which it is prone to do given that it is a gas and wants to naturally rise.

In order to avoid contamination of underground aquifers and target only
specific, gas or oil-rich zones, certain areas of the wellbore casing are
cemented. Theoretically, this practice isolates production zones from
water-bearing zones. Other areas along the wellbore are perforated,
forcing the highly pressurized materials into the targeted geologic zone
and cracking the surrounding rock.

In many environments, such as sedimentary sands and shales, this technique
has been found to improve efficiency and greatly increase yields of natural gas. The technique has also allowed operators to target "sweet spot" locations deeper underground.

This economic advantage has spurred robust and ongoing investment in
research and development while continuing to fuel America's combustion
engine infrastructure and growth which has spurred further investment.

By the 1990's shallower coal veins were being targeted and fractured
utilizing this technique, and as companies grew more proficient, ever
deeper oil and natural gas wells allowed for the exploitation of multiple
production zones residing at varying depths within a target formation. For
example, a well could be drilled to 7,000 feet, theoretically isolating
water bearing zones in order to protect fresh water aquifers, while
strategically fracturing tight sands, coals and shales along the way - all
within a single well bore.